docs: def handle_update(self, options):  # pylint: disable=no-self-use
          """ Update existing user"""
          username = options["username"]
          try:
              user = User.objects.get(username=username)
          except User.DoesNotExist:
              raise CommandError("User %s does not exist" % username)
          if options["email"]:
              user.email = options["email"]
          # False is an allowed value, but not None.
          if options["active"] in [True, False]:
              user.is_active = options["active"]
          if options["staff"] in [True, False]:
              user.is_staff = options["staff"]
          if options["superuser"] in [True, False]:
              user.is_superuser = options["superuser"]
          user.save()